[Neuronavigation-assisted microanatomical study of the facial nerve canal through the transpetrosal approach].

OBJECTIVE

To study the value of neuronavigation in the transpetroal approach, and to provide anatomic data for the protection of the nerves in the facial nerve canal (FNC) during surgeries.

METHODS

Simulated surgery through the transpetroal approach was performed on 16 sides of 8 adult cadaver heads with the assistance by neuronavigation. The anatomy of the facial nerve and the relationship of related structures were observed and the distances from the utmost external edge of the mastoid to different segments of the FNC were measured.

RESULTS

Neuronavigation was successful with all the FNC, with the mean error of less than 0.9 mm. The FNC could be divided into 3 segments, the labyrinthine, the tympanic and the mastoid segments, stretching 3.6+/-1.2 mm, 11.2+/-2.5 mm and 16.1+/-3.6 mm respectively and with diameters of 1.2+/-0.3 mm, 1.4+/-0.1 mm and 1.7+/-0.2 mm, respectively.

CONCLUSION

Neuronavigation may help protect the FNC during surgical procedures, and a thorough knowledge of the anatomic features of the FNC can be significant for preservation of the facial nerves.